STUDIES IN CONGESTIVE HEART FAILURE

Abstract

The pH and CO2 content of the blood of normal subjects and of patients with congestive heart failure has been studied before and after (a) administration of large doses of NH4Cl, (b) breathing 5% CO2 and (c) a standardized exercise. The findings in patieats with heart failure at rest were usually within normal limits, but a state of acidosis was found in 3 patients with very severe symptoms. The changes occurring after administration of NH4Cl and after breathing CO2 were usually within normal limits in patients with congestive failure. The changes in pH after exercise were usually greater in "decompensated" patients than in control subjects and the degree of change was, with 1 exception, proportional to the extent and duration of the edema. This is believed to be compatible with the presence of diminished buffering power of the tissues in heart failure. One compensated cardiac patient showed changes similar to those found in control subjects and 1 patient with "non-cardiac" edema showed changes similar to those in the "decompensated" patients. This suggests that edema itself may be related to changes in the tissues of patients with heart failure.